In Computer Science one of the most basic and fundamental data structures is the linked list, which functions similarly to an array. The principal benefit of a linked list over a conventional array is that the list elements can easily be inserted or removed without reallocation of any other elements.
In some programming languages the size of an array is a concern and one of the ways to overcome that problem and allow dynamically allocated data is using linked lists.
Luckily in Ruby arrays aren’t limited to a certain size, so you don’t have to think about overcoming that limitation.
So if array size is not a limitation in Ruby, are linked lists really necessary? The short answer to that is no; however, it’s the simplest of the dynamic data structures and it will give you a solid foundation, so you can understand more complex data structures like graphs and binary trees with more ease.
This is a linear or singly linked list like this; [ NODE(head) ] -> [ NODE ] -> [ NODE(tail) ] -> nil